Re: [PATCH -next] phy: phy-mtk-tphy: fix missing clk_disable_unprepare() on error in mtk_phy_init()

From: Chunfeng Yun
Date: Tue Mar 20 2018 - 23:04:25 EST


On Tue, 2018-03-20 at 13:19 +0000, Wei Yongjun wrote:
> Fix the missing clk_disable_unprepare() before return
> from mtk_phy_init() in the error handling case.
>
> Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx>
> ---
> drivers/phy/mediatek/phy-mtk-tphy.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
> index 38c281b..3ff9020 100644
> --- a/drivers/phy/mediatek/phy-mtk-tphy.c
> +++ b/drivers/phy/mediatek/phy-mtk-tphy.c
> @@ -841,7 +841,7 @@ static int mtk_phy_init(struct phy *phy)
> ret = clk_prepare_enable(instance->ref_clk);
> if (ret) {
> dev_err(tphy->dev, "failed to enable ref_clk\n");
> - return ret;
> + goto disable_u3phya_ref;
@u3phya_ref and @ref_clk clocks are mutually exclusive, that means one
of them must be NULL; so if failed to enable @ref_clk, then @u3phya_ref
should be NULL, and no need to disable it in fact.
But it's also no problem to disable it.
> }


>
> switch (instance->type) {
> @@ -859,10 +859,17 @@ static int mtk_phy_init(struct phy *phy)
> break;
> default:
> dev_err(tphy->dev, "incompatible PHY type\n");
> - return -EINVAL;
> + ret = -EINVAL;
> + goto disable_ref_clk;
mtk_phy_xlate() has already checked supported type,so usually doesn't
comes here, otherwise there will be a serious problem about system.

Anyway, it's better to disable these clocks when fail.
> }
>
> return 0;
> +
> +disable_ref_clk:
> + clk_disable_unprepare(instance->ref_clk);
> +disable_u3phya_ref:
> + clk_disable_unprepare(tphy->u3phya_ref);
> + return ret;
> }
>
> static int mtk_phy_power_on(struct phy *phy)
>
Tested-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
Acked-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>

Thanks a lot
>
>